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1.
BackgroundLittle is known about the extent of ordering low-value services by.PurposeTo compare the rates of low-value back images ordered by primary care physicians (PCMDs) and primary care nurse practitioners (PCNPs).MethodWe used 2012 and 2013 Medicare Part B claims for all beneficiaries in 18 hospital referral ?regions (HRRs) and a measure of low-value back imaging from Choosing Wisely. Models included random clinician effect and fixed effects for beneficiary age, disability, Elixhauser comorbidities, clinician sex, the emergency department setting, back pain visit volume, organization, and region (HRR).FindingsPCNPs (N = 231) and PCMDs (N = 4,779) order low-value back images at similar rates (NP: all images: 26.5%; MRI/CT: 8.4%; MD: all images: 24.5%; MRI/CT: 7.7%), with no detectable significant difference when controlling for covariates.DiscussionPCNPs and PCMDs order low-value back images at an effectively similar rate.  相似文献   
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目的:探讨建立一种放射治疗全身器官剂量数据库平台的可行性。方法:使用基于深度学习的自动勾画软件DeepViewer?1例食管癌患者的全身CT上勾画全身器官,然后利用基于GPU加速的蒙特卡罗软件ARCHER计算相应的器官剂量分布,最后利用Lyman-Kutcher-Burman(LKB)模型评估放疗患者正常组织并发症概率(NTCP)。结果:针对该病例,成功建立基于DeepViewer?ARCHER和LKB模型的全身器官剂量数据库,发现距离靶区越近的器官剂量越大,其中心脏与靶区间距离最小,剂量为14.11 Gy,但因其模型参数特殊,通过LKB模型计算的NTCP为0.00%;左、右肺的剂量分别为3.19和1.16 Gy,但是NTCP值却很大,分别为2.13%和1.60%。对于距离靶区较远的头颈部器官(视交叉、视神经和眼)和腹部器官(直肠、膀胱和股骨头)剂量分别约为9和2 mGy,并且NTCP均近似为0.00%。结论:研究结果证明通过自动勾画软件DeepViewer?蒙特卡罗软件ARCHER和LKB模型建立全身器官剂量数据库的可行性。  相似文献   
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【摘要】 目的 :探讨羊水粪染与羊膜腔感染的关系。方法 :选择未临产且胎膜完整的剖宫产产妇 5 6例 ,根据术中所见羊水性状分为羊水清亮组、羊水Ⅰ~II度粪染组和羊水III度粪染组。于剖宫产术中取羊水用双抗体夹心ELISA法测IL 6含量 ,取胎盘胎膜做病理检查以了解有无炎性细胞浸润 ,并记录新生儿Apgar评分 ,观察产妇术后有无产褥感染。结果 :3组羊水中IL 6含量差异无显著性 ,3组胎盘标本病理检查示炎性细胞浸润之差异亦无显著性 ,而羊水粪染组新生儿窒息发生率较清亮组明显增加 (P <0 .0 5 )。结论 :羊水粪染尤其是III度粪染是胎儿窘迫的标志 ,而与羊膜腔感染无明显相关性。  相似文献   
4.
PURPOSE: To describe and discuss the status of patient safety in U.S. hospitals. METHODS: Personal interview. This report is part of a series of discussions with a leading expert on patient safety. FINDINGS AND CONCLUSIONS: Some improvements have been made in the past 10 years. But changes have not been adequate. Continuing barriers include the punitive environment in hospitals, physicians' denial of the scope of the problem, lack of national leadership, and lack of systems thinking.  相似文献   
5.
Objective To investigate the role of inflammatory cytokines in the pathogenesis of chronic non-bacterial prostatitis/chronic pelvic pain syndrome (CAP/CPPS) patients. Methods The 38 cases with CAP/CPPS patients (18 cases of CAP and 20 cases of CPPS) and 20 cases of healthy controls were selected. The differential expressions of 40 kinds of inflammatory cytokines were detec-ted by antibody arrays in prostate fluid. Results The inflammatory cytokines which increased more than 1.5 times expression have been found. There were seven kinds in CAP including monocyte che-moattractant protein (MCP)-1, solution tumor necrosis factor receptor Ⅱ(s TNF R Ⅱ), platelet-de-rived growth faetor-BB (PDGF-BB), interleukin (IL)-β, IL-11、IL-6、MCP-2 and five kinds in CPPS groups including MCP-1、PDGF-BB、MCP-2、s TNF R Ⅱ、It-11 respectively, compared with healthy control group. The cluster analysis results showed that protein expression of Monocyte chemoattrac-tant protein 1 (MCP-1)and platelet-derived growth factor BB (PDGF-BB) were significantly increased in CAP (3.47 and 2.07 times) and CPPS (2.25 and 2.19 times) compared with healthy control group and were the final polymerization of inflammatory cytokines. The protein expression of interleukin 1 β (IL-1 β), MCP-1 and soluble tumor necrosis factor Ⅱ (s TNF R Ⅱ) in CAP group was increased more than 1.85,1.55,1.67 times compared with CPPS group. Conclusions Elevated expression of inflammatory cytokines may play an important role in the course of CAP/CPPS disease. The extent of the inflammatory response of CAP was higher than CPPS. The inflammatory factors of MCP-1 and PDGF-BB could serve as a novel diagnostic marker.  相似文献   
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中国三囊库蠓亚属的种类分布及分类研究(双翅目:蠓科)   总被引:2,自引:1,他引:1  
本文报告了我国三囊库蠓亚属Culicoides(Trithecoides)已知24种。亚属的鉴别特征,主要特征测量值以及雌虫和雄虫分种检索表。  相似文献   
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Objective To investigate the effect of angiotensin (Ang) Ⅱ and its Janns-activated kinase-2 (JAK2) signal pathway in transdifferentiation of renal tubular cells under the challenge of acute ischemic reperfusion injury.Methods Models of acute ischemic reperfusion injury were established and the level of local Ang Ⅱ ,a key element of renin-angiotensin system (RAS),in kidney was measured using radioimmunity technique.The expression of α-smooth muscle actin (α-SMA),a phenotype of mesenchymal cells,was detected by RT-PCR and inununohistochemistry methods.Renal tubule cells ( NRK-52E) were cultured with various concentration of Ang Ⅱ ,followed by blocking of PD123319,Ang U receptor 2 antagonist,and AG490,an inhibitor of JAK2 signal pathway.Results Ang 0 of kidney tissue increased immediately after acute ischemic-reperfusion injury,in time dependent fashion.Expression of α-SMA in renal tubule cells was found at 48 hours after ischemic-reperfusion injury and in NRK-52E cells treated by high concentration of Ang Ⅱ and was dose and time dependent.The peak of α-SMA expression was seen after 30 minute treatment at the dose of 10-9'mol/L,which was interrupted by both of PD123319 and AG490.Conclusions Transdifferentiarion of renal tubular epithelial cells occurs under acute ischemic- reperfusion injury.Local renin-angiotensin system may play a role in the transdifferentiation of TEC through AT2 receptor and its JAK2 signal pathway.  相似文献   
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